New Delhi– Bacteria in the mouth and gut may significantly contribute to the progression of cognitive decline in Parkinson’s disease, according to a new study from King’s College London. Researchers found that specific changes in the microbiome could act as early warning signs and potential drivers of worsening symptoms, particularly dementia—a common and distressing aspect of the disease.
Published in the journal Gut Microbes, the study analyzed 228 samples of stool and saliva from Parkinson’s patients at different stages of cognitive impairment, comparing them with samples from healthy individuals without the disease.
The findings revealed notable differences in the types and functions of bacteria between the groups. In patients with cognitive decline, harmful bacteria—many typically found in the mouth—were present in higher numbers in the gut. This phenomenon, called “oral-gut translocation,” refers to oral bacteria migrating to the gut, where they are not normally found.
“These bacteria release virulence factors—molecules that damage gut tissue, trigger inflammation, and may contribute to brain dysfunction,” explained Dr. Saeed Shoaie, head of the Quantitative Systems Biology (QTS) Lab at King’s College London. “The gut-brain axis is increasingly being linked to neurodegenerative diseases, and disruptions in this pathway may spark immune responses that lead to neuronal damage.”
Dr. Frederick Clasen, a research associate involved in the study, emphasized that it remains unclear whether the bacteria directly cause cognitive decline or whether Parkinson’s-related changes in the body create an environment that allows these bacteria to thrive. However, he noted that the study suggests these microbes may actively worsen the disease’s cognitive symptoms.
The researchers also used artificial intelligence to identify specific bacterial species and their toxic byproducts that are associated with cognitive impairment in Parkinson’s. “These bacterial toxins could serve as biomarkers to identify patients at higher risk of developing dementia,” said Dr. Clasen. “In the future, they may even become therapeutic targets aimed at altering the gut environment to protect the brain.”
Beyond potential diagnostics and treatment strategies, the study underscores the critical importance of oral hygiene and nutrition for people with Parkinson’s disease, particularly as the illness progresses.
With Parkinson’s disease notoriously difficult to detect in its early stages, these insights offer hope for earlier intervention—and possibly new paths to prevent or slow down cognitive decline in affected individuals. (Source: IANS)
